[ChromeDriver] Save PDB file from Windows build

As the preliminary step to resolve issue chromedriver:2222, modify
the build script to archive the PDB file from each Windows build.

Bug: chromedriver:2222
Change-Id: Ic8641eae20349ff436e0d1ec7ded1968fd97d4a6
Reviewed-on: https://chromium-review.googlesource.com/940169Reviewed-by: Jonathon Kereliuk <kereliuk@chromium.org>
Commit-Queue: John Chen <johnchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539899}

chrome/test/chromedriver/run_buildbot_steps.py

@@ -213,6 +213,15 @@ def _ArchiveGoodBuild(platform, commit_position):
   if slave_utils.GSUtilCopy(zip_path, build_url):
     util.MarkBuildStepError()
 
+  if util.IsWindows():
+    zip_path = util.Zip(os.path.join(
+        chrome_paths.GetBuildDir([server_name + '.pdb']), server_name + '.pdb'))
+    pdb_name = 'chromedriver_%s_pdb_%s.%s.zip' % (
+        platform, _GetVersion(), commit_position)
+    pdb_url = '%s/%s' % (GS_CONTINUOUS_URL, pdb_name)
+    if slave_utils.GSUtilCopy(zip_path, pdb_url):
+      util.MarkBuildStepError()
+
   (latest_fd, latest_file) = tempfile.mkstemp()
   os.write(latest_fd, build_name)
   os.close(latest_fd)